Get to know the hobby through this board. Check out boards all over the net. www.marvel.com is really fun. Read: Wizard, Comic Buyers Guide, Toyfare
Start slow and cheap when starting off, even if you have a lot of money to play with. Some things have to be learned the hard way despite tons of advice and better you experinece the bad side of the hobby and eBay with a low dollar purchase. When you have cruised around and bought and transacted enough to develop a trustworthy network and good feel for who provides quality goods, then you may be better off sinking your big bucks then.
Share your comic passion for reading with the younger generation. I love reading Archie and Disney to little kids; for every age and level of maturity, there is an appropriate genre of comic book out there.
Attend conventions, talk to other collectors, dealers, make connections, joke around...socialize. Comic book collectors have developed a stigma in general society due to a biased incorrect attitude of persecution levied on them by social elitists.
eBay is not the only source on the net for comic books - although it is arguably the best and most diversified source for comics. Check into all these internet storefronts...maybe you find a nice subscription discount or deal