I haven't joined Adsense yet. I'm still building my sites, so I haven't read the TOS. Is this a violation of their TOS? Apologies if this has been asked before.
If you site is made for adsense, than they won't like it. If it is not than buying traffic does not mean buying clicks, so won't be violation of TOS -- my 2 cents
This highly depends on the nature of the traffic. Spammy traffic is clearly a violation of the TOS. Please give more details.
Purchasing traffic from one of those "10,000 visitors for $10" is more a violation of common sense than anything else Play it safe and steer clear of traffic programs.
Sounds like a bulk traffic purchase from a link farm or something. It's can be against TOS (fair practices) and it can be OK - you did not provide much info. But one thing is certain: it's going to be waste of money. If the traffic is not highly targeted, your CTR is going to suck to say the least, and the earnings would be minimal. Targeted traffic, OTOH, is usually expensive and is a looser from cost stand point as well. Read some threads here from the past where people tried to devise if it's worth buying clicks from AdWords to earn anything on AdSense. No matter how you look at it - you end up loosing money. Having additional AdWords traffic may be useful if you have other conversions (other than AdSense clicks - like newsletter sign-ups etc.), but if it's for AdSense only, don't even bother.
I couldn't find anything in the TOS that mentions any kind of "spammy traffic" or purchasing traffic of any kind. I don't think there is any kind of policy issues with it. (Not that I would recommend buying bulk traffic.) If there is something in the TOS, please let me know. I like to keep on top of these types of things.