I would like to know how to offer website hosting to my clients. I would aslo like to know if anyone can suggest companies to purchase web space from.

There are literally hundreds of hosts who offer reseller plans so choosing one over another is no simple matter. From the tone of your question it sounds as though you have little knowledge about "reseller hosting". In a nutshell you buy the hosting and then sell it on to others. This brings with it a fair amount of responsibility and if you are new to hosting, making a bad choice could cost you dearly in terms of both money and customer goodwill.

Without knowing your personal level of experience my best advice would be to visit some of the hosting forums and check out their reseller discussion boards. This way you can benefit from the experience of others and hopefully avoid the pitfalls. Bear in mind that some forum users will be pushing you towards certain companies for their own financial reasons but you will find genuine advice and expertise from many board users.

There are numerous forums around, just run a search for "hosting forums" then check the boards for a reseller specific area and you'll be on your way.

You're very welcome sir.