[Evans, Marv]

I would go in and take pictures of all of the materials and construction you did. I would just walk in while the other guy(s) are working and the place is more or less open and start photographing (documenting). If she or the guy working there asks, I would tell them you are documenting your work and materials (that you didn't get paid for) for a court action later on. The might initiate some movement on her part.
The small claims court action is (was - I haven't done that for a long time) really easy. All you have to do (at least in the past) is go to the court house and ask for the proper paperwork to fill out and file. The filiing fee, last time I had to do it, was $20 plus you had to pay another $40 to have the person served. You also had the choice of having them served either by a private service company or the local Sheriff. You are notified when the person is served and receive a court date with the Commissioner. There you present your photo evidence along with your receipts, and explain why you are unjustifiably out the money & expenses. The other person presents his/her position and the Commissioner makes a judgement. Collecting the judgement from the other party is your burden, but if they don't pay and you don't file the paperwork saying they settled, the judgement remains on their credit record for 7 years (I think). Maybe somebody else who has done this lately will chime in if the system has changed. Last time I did it the limit was $5K.