Your option, as stated by Snuffy, is to buy the full version. Buying it from the Internet will be your best option, e.g.
www.newegg.com,
www.tigerdirect.com and other sites.
If you find that the price is a little stip, one of the reasons is because users don't believe in getting or buying legal copies. The lost of revenue because of pirated copies is passed on to consumers. Stay legal and get a license.