Anyone know of online mexican genealogy sites to find info on border family with Mexican/Spanish surnames?

Have a look at the links posted below, I think you would probably find the first one the most useful.

http://www.gov-files.com/public_record_search.asp?...

http://genealogy.about.com/od/mexico/

http://www.rootsweb.com/~mexwgw/

http://members.tripod.com/~GaryFelix/index1.htm

http://members.aol.com/mrosado007/mexico.htm

http://www.sfgenealogy.com/spanish/library.htm

http://www.sfgenealogy.com/norcal/resourcecenter/t...

http://www.nmcpr.state.nm.us/archives/path-gene.pd...

Hope you find something there to help you.

if you are looking for border crossing this may help, the site is ancestry.com and you can use the site for 14 days as a trial

http://southwestlegacy.com/blog/mexican-genealogy-...

and this is the actual site

http://content.ancestry.com/iexec/?htx=List&dbid=1...

http://www.freewebs.com/nosotroslostejanos/links.h...

You did not specify Texas, but this list has many resources for Hispanic American research.

And my favorite source for what is out there...

www.cyndislist.com (see her locality section).