1. As for the best combinations for beginners there really is no such thing. The best combinations are what your breeding goals are. Some people may want to breed pies while others may want to end up with a queen bee. Decide what your goal in breeding is. 700 grams is recommended at least for a male and females should be close to 1500. Normally a year to two years for males while females are two to three.
2. The type of incubator is up to you as well. It depends on how many snakes you plan on breeding and what your budget is. If you are only going to only breed one or two snakes a store bought one is fine. If you are breeding lots of snakes a store bought one will be expensive. You could make one out of a old freezer for much cheaper.
3. http://www.jkobylkareptiles.com/page.php?id=011
Hopefully this helps some.