I'm sorry that I don't actually know a place for repairing these 9900 phones in your area but I do have a band-aid solution for you.
*** Ooops sorry but I can't post links so you'll need to google this info, look on ebay.
Here is a link to what is called an external battery charger, what this device does is it charges a Bold 9900 battery while it is removed from your device, once it is charged then you re-install it and you have another day of regular use. Probably best done at night so that you don't miss those important calls. Anyhow, it really skirts the problem indefinitely but it's not a bad solution considering you've probably got something like another 23 months on your contract.
Ron