Indeed. I don't know much about the market, so I'd:

1) Follow Often1's advice and hire a consultant who is familiar with the market, players, and processes involved. They can help identify your critical business needs and your nice-to-haves, streamline your list of potential vendors, and write/administer an RFP process, and help develop selection criteria and evaluation tools (scorecards, demos, and such) to get you to the best solution.

2) If you don't want to go the consultant route, I would still put someone in charge of the evaluation/selection process, but in this case, I'd probably start with an RFI out to anyone you can think of/find in this market, outlining the core requirements (note that I would make contact, even if to a generic 800 sales line, to ensure they're even interested and so that your request gets to an actual person). Then pare down the initial proposals and do some demos with a smaller group of vendors. Make sure you have the decision-makers and the key users/SMEs on all demos comparing against a consistent set of criteria so you can make the most informed decision.

These are not all abuses, but some odd things people have expensed:
http://www.flyertalk.com/forum/trave...-expensed.html

In my experience, I knew one former co-worker who was caught falsifying expenses. She would submit a mountain of receipts to her admin every 3-4 months. It turned out that she was including expenses for personal trips (airfare, hotel, food, rental cars, etc.) and claiming them as business. Her admin caught on when she noticed that the dates for several trips corresponded to weekends or PTO, and reported her to her manager. She had gotten away with it for a while since she was apparently pretty convincing about business purpose.

In another case, a guy I knew would just expense all sorts of inappropriate things that were against the expense policy.

Another guy tried pawning off electronics as company expenses.