A quick tip: if you have file(s) which you suspect that are malicious, submit them to any of the following places:

• VirusTotal
• VirScan
• Jotti’s malware scan
• Virus.Org Rogue File Scanning Service
• Virus Chief
• FilterBit
• NoVirusThanks

Beside the fact that these sites will eliminate or enforce your suspicion (based on the number and types of detection they return), they will all send files which are detected at least by one product to the ones which don’t detect it. This is a much faster way to submit samples to a large set of AV vendors at once.

Update: added some more links

Update: added link to NoVirusThanks