Follow this thread
https://bitcointalk.org/index.php?topic=615953.0 every bitcoin signature campaign get listed there, other than that keep looking at Services section, sometimes the applicants quota is filled even before it gets added to the overview thread and lastly, there are signature campaigns in altcoin boards as well.
Yes it's true, I think there has been very clearly written on the signature campaign, you just select which one fits you, from the size of the charge, per post, weekly or monthly are also rules that must be obeyed by the participants signature campaign