I'd suggest you decide a few things now. Are you interested in getting a hatchling or a yearling or a fully matured snake? That's the first thing so you know what size enclosure you need upfront. The younger ones will start in a small enclosure and move up but if you go with tubs that isn't terribly expensive to deal with. Next I'd suggest you get all that enclosure stuff, set it up and fiddle with it for at least a week or so. If you can get that enclosure dialed in now without a snake in there it will make life easier for you and for your new snake. Lastly, think now about where you want to purchase this snake from. Your local pet store, while convenient, is not normally the best place to buy a snake. Think about attending a good reptile show or purchasing from a reputable breeder. For a new snake owner, that's usually the best way to go.