I don't want to leave you hanging without an answer, but honestly, after reading the rules, I am left a little vague, although based on the following, I think I would only enter from one of the sites.  The rules clearly state:

2. Sponsor: The sponsor of this Sweepstakes is iMedia International, Inc. (“Sponsor”), located at 1721 21st Street, Santa Monica, CA, 90404.  Sponsor is the owner and operator of the site located at www.hollywoodpreviews.com (the “Sweepstakes Site”).   


4. How to Enter:

a. During the Promotion Period, visit the Sweepstakes Site, follow the links and instructions to complete and submit the entry form  including your email address, first name, last name, address (no PO Boxes), city, state, zip code, gender, date of birth and daytime telephone number (including the area code).


Limit: Each participant may enter one (1) time per day during the Promotion Period.




So, it seems as though each entry is from the Sweeps Site.  Therefore, the way I read it, if you enter from multiple sites, you will be entering multiple times per day, in violation of the rules.

Now, this is only my interpretation.  Your best bet would be to contact the promotions company and ask for clarification.

Best of luck to you.