Yes, an apprenticeship sort of situation would be ideal, but maybe hard to come by.
It's a tricky job. Bows are delicate and easily damaged. Some bows are worth thousands of dollars. Every bow is different.
But if you want to look into it further, here are some resources.
This is a good page to start:
http://www.stewmac.com/Shopping?actn...keyword=rehair
Also, just google "violin bow rehair*". You'll find lots of discussion about materials, techniques, and tooling, mostly on various fiddle forums. And search for "bow rehair*" on eBay. There are several sellers who nearly always have a bow rehairing DVD for sale. Prices are under $10 in most cases.
There's also a bow maker back east, Lynn Hannings, who occasionally teaches classes on bow making, bow repair and bow rehairing. She also sells tools and fixtures. Here's her website:
https://www.lahbows.com/
Henry Strobel's book
Violin Maker's Notebook has a chapter on rehairing.
If you decide to give it a go, you'll want to acquire some cheap student bows and do a lot of practicing before considering taking on any paying work. eBay is a good source for cheap bows from China . It's not unusual to get Brazilwood bows of all sizes for under $40 each including shipping. And the bows are usually not that bad, especially those from known makers with good feedback like yitamusic or naural-violins-bows.