I considered the Argington crib bedding for my son (and still like it): http://www.argington.com/Argington_Bedding.html

It ended up being more than I wanted to spend and I ended up going with the rocketship sheeting from Garnet Hill.

Have you tried designing your own custom bedding at www.babybedding.com ? This is what I am using for my nursery, I am also due in february. For a non-patchy Pirate theme you could always try stripes. A bold White and Balck stripe with some red accents. Im afraid i havent any ideas for a dinosaur theme that is fresh and clean, like you want. But good luck! Take a gander at the website I mentionned, its a goody :)

The nicest graphics in the sort of themes you are looking for are available at Olive Kids.

I don't think they do crib bedding though, but that is not a big problem. All you really need for a baby are fitted bottom sheets (and sleep sacks). Garnet Hill has great ones, or you could order the ones from Olive Kids and have them sized down.

http://www.olivekids.com/

This is one of my absolute favorites... no pirates or dinos but really funky:
http://www.auntbucky.com/

http://www.etsy.com/listing/67346098/custom-made-3-pc-crib-bedding-set-dino?ref=sr_gallery_7&ga_search_query=dinosaur+crib&ga_view_type=gallery&ga_ship_to=US&ga_search_type=handmade&ga_facet=handmade

Super long link but VERY cute dinosaur cribs set.

My vote would be to skip the themed bedding, go with something solid and chic, and get your pirate on with accessories like this:
http://www.oeufnyc.com/piratepillow.aspx

Get solid or striped or any other geometric or graphic sheets you like. Buy pirate or dino accessories, wall art, etc.

You will hardly see the bedding unless you use bumpers (ducking!) so do not obsess over the sheets.

Agree with the people who suggest solid or striped (i.e., basic) crib sheets. You're going to be changing and laundering those sheets a *lot*. Get a few sturdy crib sheets (at least 3 or 4) (and waterproof mattress pads), because they're always going to be in the laundry. Lands' End made great crib sheets when I was in the market for them.

Then go nuts with pirate/dino accessories!

Just get plain white fitted sheets from Ikea. Lots of them. And a bunch of waterproof pads. When you make the crib, layer a pad, then a sheet, then another pad, then a sheet, then another pad, then another sheet.

When something bad happens in the middle of the night (and it will - and there will be bad nights when it happens multiple times, so you really do need 3 or 4 total layers), peel off the top sheet and pad. No hunting around for another sheet. This is very wise advice from one of the nurses in the maternity ward where I delivered (apparently it's a common nurse trick on all kinds of wards).

Sheets get peed on. And vomited on. And explosions occur. Bleach is sometimes a really useful thing.

And bleach isn't kind to cool fabrics. One of the moms in my new moms group had a total breakdown at one meeting when our kids were about 8 weeks old. She's invested a lot of emotional energy in decorating the nursery, making her own bedding, etc. And in return (mind you, this was through the lens of massive sleep deprivation), her child kept having massive explosive infant bowel movements. Her hard work was ruined, and at that vulnerable time, it really hurt more than it should have. It was really stressful for her to have something that she put so much energy into that just didn't work out.

Get awesome curtains and art. Get cool wall decals. Bust out the paint and do cool things. But really, don't worry about the bedding too much.

I found this DIY crib sheet tutorial -
http://www.dana-made-it.com/2008/07/tutorial-crib-and-toddler-bed-sheets.html

I've been meaning to try out, but haven't yet. But it looks pretty simple and straight-forward. I'm not doing any particular theme for my nursery, but its just hard to find sheets that aren't boring (without having to pay up the waazoo). You can get the fabric of your choice and make a few.

I agree with Olive Kids bedding, we just got this one after I went through a ton of options for our sons Pirate room, including making it myself: http://www.olivekids.com/product_BD-PIRA-216/Toddler+Bedding/Toddler+Sheetset/Pirates%21.html
I still plan on making curtains myself since I'm not into the whole matchy-matchy overly themed stuff and plan to use red/white stripes and a black/white modern looking damask fabrics to compliment the bedding.

My advice (I'm due february and going through the exact same thing. We thought about dinos or space/rocketships and ended up vetoing both) is google the heck out of more modern fabric store and scan all their fabrics. I did recently and saw a few more blocky modern dino prints. And then make your own sheets. SUPER easy if you have a sewing machine and can sew a straight line. But as others have said, I'm making a crib skirt/curtains etc in my own fabric I buy then just sticking to solids for the sheets since they'll get the wear and tear.

It might be worth checking bed bath and beyond too. I remember seeing a really cute solid color, blocky dino shower curtain. They may have sheets or something similar you could repurpose?

I agree with an above poster. We're also due in Feb. and have a dino "themed" (though I didn't plan on a theme) nursery. I opted to go with solid sheets since kids pee and puke on sheets so often anyway, and I found lots of cute dino accessories.

Cocalo Baby has a really cute Dinosaur set...check it out:

http://www.cocalo.com/item.asp?id=1256&brand=1&g=4&coll=&cat=1

:)

I have a workroom that will make crib sheets to fit your mattress. I also have a resource for contemporary pirate & dinosaur prints. The same fabrics can then be used to make window treatments, bumpers, etc. along with contrasting stripes & plaids. Mixing it up adds sophistication & longevity.