Why are you heading down to Saguaro first? Wouldn't it be less driving to head to Santa Fe then loop to Jerome and then down to Saguaro and back to Phoenix? This totally avoids Los Cruces.

If you are looking for other things to do in the Santa Fe area, give a little information on what you are interested in, Native American history/culture/ruins, hiking, art, etc.

we arrive before noon and figured to camp in the area of the nat'l park outside of Tucson - that's why we are headed to Saguaro first for a couple of days. If we take rt 60 from AZ into NM is that a decent way to travel? Not necessary to be in the midst of the tourism mecca but, do wish to see Native American sites/ruins, do a bit of hiking, any shopping will be in Santa Fe and Jerome. Not sure of rock formations between NM and AZ...some are trying to get us to travel further north than I had considered.. not sure, as would like to enjoy what there is to see.

Near Santa Fe check out Bandelier National Monument, very interesting ruins, nice place to hike there is in a section 5 mi closer to SF called Tsankawi. About 10 miles east of Flagstaff off I-70 is Walnut Canyon, Between Phoenix and Flagstaff is Montezuma's Castel and well (not far from Sedona)

1) It will be very hot around Tucson/Saguaro in early September. Are you prepared to camp/hike in the heat?

2) Not sure what you mean by "rock formations between NM and AZ" but you may want to consider bypassing Saguaro and camping at Chiricahua National Monument instead. It's a higher elevation with very interesting rock formations. Plus it's got plenty of Native American history - but not really any sites/ruins. You could also check out Cochise Stronghold and Fort Bowie National Historic Site in the general area. I spent several hours at the Fort Bowie site, very interesting, even more so if you read up on the history of the area ahead of time.

http://www.nps.gov/chir/index.htm
http://cochisestronghold.com/
http://www.nps.gov/fobo/index.htm

3) From Santa Fe to Grand Canyon, I would head north just east of Flagstaff on Hwy 89 and drive through Sunset Crater Volcano National Monument and Wupatki National Monument, then enter the Grand Canyon via the East entrance.

4) There are so many Native American sites/ruins that you can't possibly see them all.

Casa Grande is about an hour from Phoenix, not far off I-10
http://www.nps.gov/cagr/index.htm

I'm not familiar with anything in NM but there are a number of national park/monument/historical sites near to your route.

El Morro
http://www.nps.gov/elmo/index.htm
Bandelier
http://www.nps.gov/band/index.htm
Petroglyph
http://www.nps.gov/petr/index.htm
Pecos
http://www.nps.gov/peco/index.htm

barb- I know Hwy 60 very well, I travel it a few times a year from NM to the White Mountains and I honestly never tire of the beauty. It is an unbelievably scenic drive, coming your way, once you get into the Salt River Canyon. I would have a few suggestions.
First would be to either take Hwy 60 to 260 and then back to 60 toward Pinetop/Lakeside OR cut off Hwy 60 in Carrizo (onto 73) and take that to 260 and then back to 60. in Springerville The drive over the White Mountains (Hwy 260) is FAR more scenic then driving through Show Low and on. Chances are you will see elk, deer, pronghorn (mistakenly referred to as antelope) and maybe even bear. There are wonderful campgrounds in Greer, Arizona, which would be about a 4 1/2-5 hour drive from Tucson. Greer is known as the Little Switzerland of Arizona, for good reasons. The headwaters of the Colorado River begin here. The oldest continuously run lodge in the state is also located here. There are thousand of miles of hiking trails in this area. If you do go this way, be sure to stop and ride the chairlift up to the top of Sunrise Ski Mountain (elevation 10,000'), you can see clear to NM, the Petrified Forest and beyond in an almost 180 degrees view. You can hike back down (about an hour) or ride the lift back down. You can check my screen name for photos and trip reports.
There are some ruins around Springerville, the Raven ruins and Casa Malpais but check on line to see if you can access them.
Once 60 crosses into NM I'd take that as far as Quemado then take 36 to 117 and drive through El Malpais coming out in Grants on I-40. El Malpais has spectacular rock formations, a natural bridge, ice caves, ancient lava flows and more. There are hiking trails in this National Monument as well as some campsites. If you do take this route, make sure you fill the car up in Eagar before heading out as services in Quemado can be spotty and there is nothing, and I mean nothing, except Quemado, until you get to Grants.
El Morro is supposed to be quite spectacular for Native American ruins and can be detoured to from Quemado.
Acoma sky pueblo will be on your way off I-40, before ABQ.

Do recognize that Hwy 60, reaches elevations of about 7500' and if if you go over the White Mountains on Hwy 260, you will reach elevations of 9000 feet and be driving through the largest stand of Ponderosa Pine Forest in the world.

If you need any recs for anything, back country drives, hikes, etc. I would be happy to help. We are headed back to Greer again the end of July for two weeks and can't wait!