I'm forum crashing here, but I saw the title in new posts and since I love birthdays, here are a few ideas:
--First, I think the special dinner idea is great. I love having my favorite homemade foods on my birthday, even if it's a meal we had last week.
--I find that even the act of simple decorations (e.g. paper streamers, paper stars, balloons, a homemade happy birthday sign on the door, etc.) can make a day festive. If you can get to a dollar store or pharmacy, you can usually find this inexpensively. Or use scrap paper to make your own. If you don't like your handwriting (I don't sometimes!) you can cut letters out of magazines, catalog, or junk mail to make signs.
--Can you get or make some yummy coffee and have it for breakfast on his birthday?
--If he likes trivia, look up coffee facts and trivia on the internet and decorate your home with them (or hide them in fun places for him to find, like under his toothbrush). Or if has favorite bands or genres of music, include fun facts about those too.
--If your computer has a CD burner, burn a CD of songs that he introduced you to (through his love of music) that you love now.
--A photo collage of the 3 of you sounds like something he would really like. This could be a wall thing or you could get a coffee cup that you can put pictures into. Starbucks has one (http://www.starbucksstore.com/products/shprodde.asp?SKU=271241) and other places probably carry it as well. Alternatively, you could order a coffee mug from walgreens, snapfish, or a similar company etc. with a picture on it. It might not come in time for his birthday, but could be a fun belated birthday present.
--My DP always enjoys getting a "top 10" list...like 10 things that make you a great partner or 10 wishes for you for the coming year (which could include big things like "I hope your dream of XXX comes true" or little things like "I hope your favorite band releases a new album...")
--A coupon book to make the birthday last longer with fun coupons like "good for the cake of your choice made by me" or "trading chores day" or "pick a book that you'd like to discuss and I'll read the whole thing even if it's not my type of book so we can discuss"
I hope your DH has a great birthday and that you all enjoy the day. My favorite part of any birthday is spending time with my smiling partner and adorable DD. Your DH sounds the same so I'm sure whatever you do or don't do, he'll be glad to have time with you and your DD that day. :-)