I found this link off of the New Mexico Culture Net, a site called "The Civil War in New Mexico". Items included on this site are soldiers and weapons, photos and sketches and essays and letters. There is also an extensive link section and a timeline. It's worth a look.
The New Mexico Culture Net itself is fantastic site. In the future I'll probably post other links from that site.
Link to the New Mexico Culture Net
Link to the Civil War in New Mexico