I am about to start a new adsense website. The exact keyword I am looking has .com.net.org all taken. So I was looking at other options. then I seen that the .com is up in october and the guy that built it seems to have done very little with it and it does not rank well. I am thinking should I take a chance and wait until october, build other sites and then try and snatch the .com or should I just build the site and use a different keyword? would it be possible to build the site under a keyword now and if I did get the .com in october I could transfer it to that then?
maybe you could try to contact the site owner and query him/her about that, if he/she is did not maintain the website, maybe he/she will consider your offer, use the service provider such as godaddy to bid on the website, i've done this before for one of my client, and he got the website for $xx only
I agree with YoHanip's idea, although waiting until October may be a ok decision. Just get some cash while waiting - so you can boost that site.
Your best chance of getting the domain is to contact the person. Lookup his email or phone number from the whois details.
I would wait till october and would build the site locally so you can put it up ASAP when you got a domain. When the owner extends the domain then contact him/her not before, if they see someone is interested then they will extend for sure.. (Some hosts also extend automatically - so the choice would also depends a bit on the kind of host )