If you decide that you want to take on most of the task yourself, I can give you a small bit of advice. I am new to Rails, with no programming background at all, other than some basic JavaScript and PHP stuff that I have done in the past.
In the 3 short months that I have been learning Rails, it has been awesomely fun! Ruby is a great language and Rails is a really fun framework to work with. I started literally from the ground up and have been steadily learning each and every day.
In the very beginning, I bought 3 books. The first was the Agile Web Development with Rails book. This book is a MUST for learning the core concepts of Rails. Next, I bought the "Build your own Ruby on Rails Applications" book from Sitepoint. This book really helped me to get the basics going and understand what I was doing. I also bought the "PickAxe" book, which has been an excellent reference guide for Ruby. All I can really say is to read a lot, build some small, basic things to get a feel for Rails, and then go for it.
So, here is my advice:
1) Buy some books to help you with the initial learning of Rails. Bookmark the Wiki and API as well! 2) Check out some of the great screencasts out there! (Railscasts and Peepcode are unbelievably good!) 3) BUILD SOMETHING! Get something up and running and work on it as you go. Don't worry so much about the details in the beginning, just get your idea down on paper and build it, tweak it, refine it as you go. The details will come along as you get more experienced. 4) Get involved in the community, they are a tremendous help to solving problems, and helping lend a hand!
I think that if you go in with the mindset that you can do it, you will. It will take a lot of hard work and learning, but the rewards of you building it yourself will be much greater than hiring someone. I think the route you choose depends on your ultimate goal. If this project is simply for your own financial gain, then maybe hiring someone is the way to go. If you are doing it to learn programming, reward yourself with a finished project, and gain knowledge, then you should certainly give it a shot!
Good luck with it!
--Cory