fuel gauge broke

[ibanezxguy]

i was out saturday playing a little too rough with my car i guess but i started out with half a tank of gas and after i was done i looked up and thought i might need gas but it said i had a full tank.... and its been there for 3 days now ive put fuel in it to see if that would fix it but it didn't so i guessing i broke the sending unit/ floater thing.  Is that right?  If so how much do these cost?  None of the part stores around here can find me one.  and is it under that little silver pannel in the trunk on s14 models?  Thanks
Adam