Best place would be the barrel forum down in the equipment section.
Booms are very nice barrels for sure but for starting out not necessary. You can find them used in great nick in b/s/t.
Majority of barrels will function the same, biggest difference is the porting style, holes down the forward half of the barrel. They let the air escape, effects sound signature and within reason efficiency. Personal favorite is the dye ultralites. But barrels are a big personal opinion subject.
CP does make a good barrel for a good price, as does Lurker with the Eigenbarrel. LAPCO's barrels were always good tubes as well, although far less popular among the speedball crowd. Those are all options available in the $40-60 range. Beyond that pricing, if it were me spending my money, I'd be looking at a used barrel kit to cover multiple paint sizes.
Disruptive one piece or two piece. Why buy a cheaper barrerl for "starters" when most modern markers are cocker threaded (atleast the most popular ones) so get a good barrel to start with so you dont have to buy a nicer one later. dye boomsticks are overpriced. Disruptive, lucky barrels for no sizer barrels, deadlywind barrel if you want to use freak sizers.