LOST DATA ON PEN DRIVE

Question

I have an integral 4gb pen drive that I used to store data on. My laptop (uses windows xp) froze and nothing could be down to unfreeze it so I had to removal the battery etc and restart it. When I went to access the pen drive all the data that was stored on it was missing. If I view the properties for the disc it shows no free space and no used space available. I also get a message asking me to insert a disk into drive f. I took it to PC World and another place that does repairs and both places say that the drive has been "burned" and al data lost. PC World used another couple of programmes and attempted to access the files from my laptops recycle bin (I had stupidly tidied up my trash - yes I know that was silly but that is what women do!!!!)but I could only recover about 10 files, the rest were unreadable. PLEASE can anyone help me - the work on the disk has been done over the last few years and is essential for my work - can anyone tell me if I am chasing a lost cause here or is there some way that the files could be salvaged on my pen dirve!!!!!!!!!