With
Bitpim, you can sync your contacts, photos, and more. It's not as graceful as iSync, but I have used it successfully with Samsung and Sanyo phones. Sorry, I have no experience with LG phones and Bitpim, but the VX6100 is listed as supported.
You will need a usb cable if you do not already have one for the phone. They are available on eBay, at RadioShack, and from specialty retailers like
3Gcables.
Do be aware, Bitpim is great but it's still in development release (current version is 0.7.31). It should work, just don't expect it to be perfect.