Part 380 of the DOT’s regulations (14 CFR 380) requires all persons who wish to arrange public charter flights to first submit a charter prospectus to DOT which contains information about the proposed charter program.
The FAA, a division within the Department of Transportation (DOT)certifies air carrier operations. Continuing approval to operate also comes from the DOT itself in the form of determining economic viability (it also includes being certain airlines operate with insurance!). A real airline is not authorized to access any funds received from an air traveler until the first leg of the purchased flight is operated. If an independent air carrier or tour operator (those not accepting payment thrugh a bonded clearing house) is processing your payment prior to your first leg of travel, this is a good sign they may be financially strapped and you are exposing yourself to disappointment.