I ended up using money as a motivator. All the pc's came up with good backgrounds and reasons for being in DL. As an added bonus, i allowed any pc who had a background in which they grew up in diamond lake, I gave them knowledge:Local as a class skill no matter what class they took. (which turned out to be pretty helpful to a few).
At the start of the adventure, I only let them start with 1d10 silver and 1d10 copper pieces of their starting money. (after they had bought all the wanted too). then i went through and trimmed their character sheets of a few things. Namely consumables, like rations and torches and such.
This way, they started out in a rough town, down on thier luck with only a few pennies to rub together. I had the bard type character win a map of the wispering cairn in a game of chance. and after hearing about the other adventures in town exploring the the other cairn, he thought he might be able to find some riches in the wispering cairn, so the put together a group of people who likewise needed money and the rest is history.
It all worked out really well. The PCs are really motived to secure some funds, not enjoying having to go to town to buy poor meals instead of teh standard fare. Its actually interesting to watch them budget, selling a silver ring they found so they can get a weeks worth of meals and some other misc supplies. Its a bit of a nice change from dealing with high level PCs who have enough gold to live in the lap of luxury and can wreck the economy of any small town when they stop by.
Plus they have really taken to fixing up the old mining office from dragon #333. They are spending their downtime (while pc's heal up and rest) to fix up the place.
Overall it has started out really well. Thanks for the suggestions all!