Henry wrote:

3) Best web sites or books to help me get started.

http://www.thekrib.com/Plants/CO2/

5) Any worthwhile advice from people with experience.

Success with CO2 is all about efficiently dissolving the CO2 in the water and
keeping it there. If you have done well with DIY, then you have experience in
this area. But remember to design your CO2 and filter system to minimize surface
agitation while still allowing adequate circulation.

I got excited about using a cannister filter to inject the CO2, since it was a
simpler solution than having a separate reactor. Unfortunately, each bubble
makes a smacking noise on the impeller, and we value quiet more than simplicity.
If this small noise is not a problem for you, definitely use the filter. It's
one less piece of gear to clean and maintain.

Since a CO2 bottle must be used upright, buy the biggest tank you can still
hide. In my case that is a 10 pound tank. A 20 pound tank would last twice as
long (or longer, since they are often not filled all the way), but it is so tall
it would have to be left out in the open. It's pretty darn heavy, too!

Any beverage supply shop can sell and refill tanks. Look for places that sell
soda fountain drinks. Welding supply shops usually carry it too.