Hi there,
If you travel a lot domestically in the US, there are some travel websites who can provide cheap travel tickets such as 'Save on Airline Tickets for US cities', 'Last Minute Cheap Airline Tickets for Los Angeles' and 'Last Minute Cheap Tickets'.
Other good travel search sites are Expedia and Priceline to find also hotel
accommodation, car hire and so on.
Personally, when checking deals and providers, I do my research and check out independent reviews by people to get a good idea of a competitive deal even if the deal looks tempting.
Hope this helps
VacationBuddy