With most cases, the thing to remember about spiders is that they are predators - which means they usually set up shop near pathways their pray are active on. If you find yourself with excessive spider webs, the first thing to do is look for where the spiders' food may be entering your house, and seal it off. This may mean repairs to screens, or using caulking, spackling, or foam to seal up holes. Be careful though - there are some areas of your home, such as crawl spaces, that need ventilation to avoid black mold.
These white, puffy sacks are a sure sign of Black Widows on your property.
Rarely, infestations do occur. When it comes to Recluse spiders, this could be a lethal nightmare. Just google "recluse spider bites" to see how vile these wounds can be - but don't do it if you are in any way squeamish.
The Brown Apache spider, a close relative of the Brown Recluse, here in NM - these are extremely dangerous, as their venom rots human flesh in a massive way.
Wolf spider, carrying her young. One of the more common spiders in New Mexico, largely harmless to people.
In general, spiders rarely 'infest' a space - when this does occur, it's usually because of very abnormal conditions, for which you may want to call a professional. Additionally, some clients of ours may feel more comfortable in working in the dark areas of their homes, such as crawl spaces or attics, only after they've been treated by a professional ensure there are no black widows or brown recluses. Most often, a quick phone call is the best place to start.