Heater just stopped working.

I have a 98 Olds Intrigue and my heater just stopped workin last night not sure what might have caused it...was just wonderin if anyone might know...I'm also havin problems findin my fuse box?..Could someone please help me out.

the fuse box is under the hood right above the passenger side front tire. I figured mine being stuck on was a relay issue so you might want to look into that.