is there any way to get a better sound system in my truck?

[BrianBannon]

I drive a 1993 Toyota Tacoma pickup. Its nothing fancy but i would love to get better speakers in it. Here is my problem. It does not have door speakers. And currently has small speakers in it.. i wanna say like 2.4in.... nothing fancy... i know its an old truck but is there anything i can do? Its a single cab so i cant put anything behind the seats. Do you guys and gals have any suggestions? or am i just stuck with having to have just the tiny speakers in it?

thanks for all your help!

BB