I do know of two web-based solutions that might be worth taking a look at:

• Map Rectifier from MetaCarta
• MapWarper created by Tim Waters

I'm pretty sure Tim Waters open sourced his code, so even if these particular tools don't suit your needs, looking at their source might give you some insights.

Sorry, I can't post more than one external link because I am apparently less than reputable.

I do know of two web-based solutions that might be worth taking a look at:

• Map Rectifier from MetaCarta
• MapWarper created by Tim Waters

I'm pretty sure Tim Waters open sourced his code, so even if these particular tools don't suit your needs, looking at their source might give you some insights.

Sorry, I can't post more than one external link because I am apparently less than reputable.