I am looking for Torrent Creator with Web seeding ability. Please tell me if there are any available to me under Ubuntu or any other place.
Most torrent programs have the ability to create a torrent in the menu, my personal favourite is qBittorrent for it's simplicity and sheer speed of use...
Transmission is the default torrent client in Ubuntu. To create a new torrent, go to file menu and choose the new option (Or press Ctrl+N).
Like most torrent clients, it also supports seeding.
dottorrent-gui supports this: https://github.com/kz26/dottorrent-gui
You appear to be suffering from a misconception. Torrent clients/creators don't have Web Seeding capability. Webseeding is done with an HTTP or FTP server. The client may or may not be capable of downloading from a webseed. For a further understanding you may wish to review What is "web seed"? and http://www.bittorrent.org/beps/bep_0019.html