You need to be 100% sure of what you're doing when flashing a BIOS...I'd suggest never using a generic flash program--the company will TELL you which program to use...and ALWAYS backup the current BIOS before flashing (all programs I have ever used allow for this). You may also need to enter BIOS setup and enable flashing/disable flash prevention. I also like to disable all caching/shadowing as well (restoring default settings afterwards).
BIOS Agent is THE program for identifying your motherboard/BIOS version..very simple little 230 kb freeware program which will gather the info in about 3 seconds:
http://www.esupport.com/biosagent/index.cfm
You should then be able to use the information to locate the company website but if you really aren't sure then post the info BIOS agent gives you at:
http://www.wimsbios.com/phpBB2/viewforum.php?f=33
Always remember that the manufacturer of your motherboard is not always, and often not, the company responsible for the BIOS (with OEM etc it can get a little confusing).
Good luck.