Car squeaking, please help

[Sinistral]

Within the last few days my '87 has developed a squeak. I've been able to narrow it down to the left side, but I'm not sure if it's a front or rear issue (or both).

I'm almost positive it's not the brakes because the squeak is constant. It actually seems to have gotten worse (or more apparent) as time goes on, which has me worried. It seems to be more audible at lower speeds, although I suppose that could also be due to less tire/wind noise.

Anybody out there have any ideas on what it could be? And if so, any solutions?