As with the other responder I would definitely start with a faster lens, but I'll continue here on the basis you won't be running out to get a 70-200 F2.8 in the next hour.
Therefore I will try to be a little more constructive.
I would set ISO to 1600, and don't worry, it will work.
I would take some saple shots, and manually adjust WB. On the K10D it is really easy. Take a test shot, then pres the Fn button, and select WB. Yoou will see your image with the WB menus superimposed on it. Now make a change, and you will see your image change interactively.
Adjust the WB as close as you can to neutral, but I would leave it a little warm, i.e. color temp less than 5000. YOu may need to compensate a little for the yellow in the sodium lights also.
I would set sharpness to neutral, and have the raw button set to give you JPEG plus RAW when pushed. This is because sometimes at 1600 ISO, raw can be a little better but max resolution JPEG should let you make a good 8x10. If you see a really good moment coming push the raw button so you have more to work with