I spend about 7hrs in 1 day, about once every 3 months, cleaning my car from top to bottom. Wash, Clean, Polish, Wax, Wax, Wax, Wax... lol. Plus a standard wash once a week, and every month a top up of wax (OCW at the moment)
I love doing it - it's all part of the fun.
IMO, you can do a very good job with very basic knowledge - so long as you buy the right products that complement each other - and I'm more than happy with my results. I spent £160 on cleaning products last year, and most of it should last me another year. (bar the shampoo and such)
If you're REALLY into it - get on to detailingworld - learn, and even get shown how to do a good job by a member who lives close to you! - http://www.detailingworld.co.uk