I'm currently looking to create squeeze/landing pages for

I’m currently looking to create squeeze/landing pages for a bunch of informational materials I’m marketing through my site, however as this is new to me I’m not sure if this should be done with plugins (if so, which ones) or by hand.

Also – I’m not sure if the landing pages should be run under a separate domain, or if I could just run them through my primary WordPress install.

Thanks very much in advance for any insights!