if it is the full version you should have the plugins, and they get installed automatically now (rather than a separate installer as in previous versions). i would call adobe if you didn't get the cycore effects with the full version.
if you downloaded the trial, i believe it doesn't come with the extras like the cycore bundle, so you would need to purchase the full version or the hd cycore effects from cycorefx.com.
if you are on a pc or powerpc mac (g5, g4, g3.) you may be able to move the cycore effects from version 7 to cs3, but i'm unsure of compatibility...
if you have an intel mac, you can try the same, but you will need to force ae to run under rosetta powerpc emulation (an option in the get info window for the application).