Hey Sumeetha,
glad to hear about you interest in ax..
if you have access to partner source, then you should be able to download the ax09 vpc from: https://mbs.microsoft.com/partnersource/deployment/methodology/vpc/vpcimageax2009.htm?printpage=false
if you are not member of a partner company, then you would have to get it though with either Microsoft directly (http://www.microsoft.com/dynamics/ax/request_more_info.mspx) or one of their partners.
i don't believe that trial or developer edition is available as yet.
however, Microsoft have released tons of demos/videos, along with some really good white papers, i would strongly recommend giving them a read before you actually start using the software.
http://www.microsoft.com/dynamics/ax/product/default.mspx
also if you have access to msdn you should be able to access the ax development center on:
http://msdn.microsoft.com/en-us/dynamics/ax/default.aspx
let us know if you have any more questions.
regards,
Mohammed Rasheed
www.dynamic-ax.co.uk