[WTB] - PDF converter script

[domainsmine]

Need a pdf converter script.

Any file type to pdf converter.
Any pdf file to word, pic,excel,ppt converter.

Any url to pdf converter .

Does anyone know a free open source script that does it.

Am ready to pay for below goodies if someone can modify an open source script -
People should be able to upload files, and get download links in mail and on site.
Users should be able to register and should have a quota for downloads. Conversion should be such that can be limited to user groups / users.
The converted file should be shared on site like scribd/idocs .
It should have a DMCA section.
Ability to change background image, add logo to site , facebook and twitter integration , paypal integration.

Let me know how much time and money for modification.
Also let me know anny free scripts available, to see whats added over and above .