I recently started a new position on a Wednesday, This is a salaried position.
I worked 8 hours on Wed. 11 hours on Thurs and Fri. I had to attend a manditory meeting on Sat and I was there 8 hours. When I received my 1st check, the only paid me for 24 hours. I was told that they only pay for time worked Mon thru Fri. Is that legal?
Secondaly. Is a company that you travel for required to pay your travel time? If I fly out of town and they pay for my time traveling, Do they have to pay for my travel time home for time off?

"Salaried" and "hourly" are just payment methods and do not mean much legally by themselves. Are you Non-Exempt (must be paid overtime) or Exempt (no legal right to paid overtime)? The rules are very different for these two types of employees. Non-Exempt employees must be paid for all hours worked, while Exempt Salaried employees are mostly just paid their salary no matter how many hours are actually worked.

Under the federal portal-to-portal act, commute time is normally unpaid although there are a very few exceptions.

Assuming that you are Non-Exempt, the following is the related travel rule.

29 CFR 785.39 - Travel away from home community.Travel that keeps an employee away from home overnight is travel away from home. Travel away from home is clearly worktime when it cuts across the employee's workday. The employee is simply substituting travel for other duties. The time is not only hours worked on regular working days during normal working hours but also during the corresponding hours on nonworking days. Thus, if an employee regularly works from 9 a.m. to 5 p.m. from Monday through Friday the travel time during these hours is worktime on Saturday and Sunday as well as on the other days. Regular meal period time is not counted. As an enforcement policy the Divisions will not consider as worktime that time spent in travel away from home outside of regular working hours as a passenger on an airplane, train, boat, bus, or automobile.