If you are looking for basic sandwiches on wheat and white bread w/ basic fillings such as Ham, turkey,roast beef and cheese cut into triangles...Super Walmart does a great sandwich tray....approx $27 Requires 24 hour notice....
If you want to get a little fancier go to The Picnic Company...I have used them many times when I have catered meals for clients.
Their Tuna and chicken salads are wonderful as are all their fresh salads and pasta salads.
you could also call Jason's Deli, or Paradise Bakery....
They both have multiple locations around town