I would say check out Vista Print -
http://www.vistaprint.com
They have cheap printing, and in the business section have lawn signs and flyers as well as many other option.
The easiest way to save money for your friend, is for them to do the leg work themselves. Meaning place the signs and flyers, stand at busy street corners, etc. Paying a teen friend after school, or a relative is better than hiring someone else.
I know for example, the guys that stand outside apartment complexes make about 22 an hour to wave those damn "now leasing" signs.