What are the prerequesits for SMS installation

Have a look at following:
http://www.microsoft.com/technet/sms/2003/evaluate/r2.mspx

Does it reqire any supporting software .Say ADS etc.

Farhan have you installed and tested this software...

No, SMS 2003 does not require Active Directory, BUT there are advantages to using Active Directory Domain Services with Microsoft Systems Management Server (SMS) 2003. The advanced security mode of SMS 2003 requires Active Directory and provides easier account management. If you have Active Directory, you can use the Active Directory site boundaries as the SMS site boundaries. Extending the Active Directory schema also provides many benefits, but is not required.

Have a look at following FAQ's
http://www.microsoft.com/technet/sms/2003/evaluate/faq/default.mspx

Personally I have never installed and tested SMS, but in my organization it is implemented.

Can i have the software packages required to install SMS.

Download the 120-day trial software, you're automatically registered to receive valuable resources delivered at strategic intervals throughout the software evaluation period.
Download it from:

http://www.microsoft.com/technet/prodtechnol/eval/sms2003/default.mspx

Thanks farhan.

While installing if i need any help i shall post a Q and put the path here for your help...

Thanks Sharath