you could try using Google friend connect launched recently. Definitely adds viral functionality as people can invite their friends and you can push their activities on your site to open social containers to which they belong. For example id love if you could push my reviews on your site as my updates on Orkut (sorry am from india not a big FB fam:))
thinkpython.com - although its supposed to be an introduction to programing using python but it suited me really well, even though I was a C++ programmer for four years. You can skip the basic parts and run through some of the explanations which are for a new programmer but all in all a rapid start guide for python.
ours is a startup thats a webapp that integrates with the real world very closely. Almost all our revenue actions happen off line. The business is very people dependent with the web providing us platform to showcase our capabilities and reaching out users.
I think age really is an important factor in starting business and it works to ones advantage depending on the kind of business as well. For starters, I don't think there is any substitute for experience and like kyro said, it also gives one a certain level of maturity in dealing with issues like finances and emotions. Especially family, which tends to get ignored (to say the least) if you are a twenty something hacker working 28X6 in your mum's garage.
I have personally felt a little off balance seeing people lose color when they see me in person. Since my business requires a lot of off line interaction with people, they generally become a little wary on seeing someone in tees and jeans. If you are going for such a business, your age, and more importantly your maturity will be your biggest asset.