Here are a few links to free coop plans, if you're thinking of building your coop from scratch. You might want to follow one of these plans completely, or they may be a jumping off place for you to draw up your own plans and create something unique and one of a kind.
Make sure you understand all the requirements your chicken coop has, as well as other considerations to keep in mind in regards to building a coop.
If these links don't offer you enough of what you're looking for, there are LOTS of resources out there both online and in books. If you don't want to buy plans, see if your local library has books on coop building and design. Stroll around your city and look at the hen houses others have built. Go on a coop touring event and talk to people who have built their own coops. There are lots of free resources out there, if you take the time to search.
You can also read my diy chicken coop story (and see lots of pictures of the process)--and most importantly, learn from my many mistakes (although I did make lots of mistakes, it's also safe to say that I knew NOTHING about building ANYTHING more complicated than a very rough bookcase and I've got standing, functional housing for my girls at the end of it all...so if nothing else, if I CAN DO IT, ANYONE CAN!!)
In the meantime, here are some links to get your creative juices flowing:
Build Eazy Chicken Coop Plan
Portable Mini-Chicken Coop Plan
The Stealth Urban Chicken Coop
Organic Gardening's Movable Coop
And if you want more inspiration, check out these chicken coop photos!