TAs are pretty much useless for domestic air travel (unless you're looking for an air+hotel/car/entertainment package). "Good travel agent" is an oxymoron ... all the ones I knew got out of the business.

Base fares out of LAX? Let's see if I can beat $238.

LAX-DAY AA/CO/DL/NW/UA/US $198.
LAX-IND AA/CO/DL/NW/UA/US $198. DL/UA require Sat. stay; AA/CO/NW/US let you return the next day.

LAX-ATL UA $337 (WOE14N6X); CO $198 (TOE14SNX).
LAX-DCA UA $414 (WL21M77N|WLE30M7N); AS $198 (VX14FSN9).
LAX-PHL UA $248 (TE14ONQ4); AA/CO/DL/NW/US $198.
LAX-CMH UA $238 (WOE14N10); AA/CO/NW/US $204.

I couldn't find anything where UA offered a lower fare than their competitors.