I would like to hear about any programs or teaching products that provide best methods for developing more business from existing clients. Thanks

Interesting question.

If you are willing to make the investment, Targeted Account Selling is a wonderful methodology. Their site is: http://www.thetasgroup.com/

My favorite, as it is so simple and elegant, is Buyer Facilitation developed by Sharon Drew Morgan. Her methodology puts sales people into a collaborative role with clients so that opportunities are identified in partnership with clients. I suggest that anyone in sales or sales training read her book "Selling with Integrity. Her website is: http://sharondrewmorgen.com/

Last, no amount of training can replace the simple rule of thumb to spend time with clients at their place of work when you are NOT SELLING. Dropping in for a cup of coffee will allow you to see clients actually working with your products, to hear and see frustrations they may have. If clients know you actually care about their success, that you have taken time to learn of their challenges--they will trip overthemselves to use your other services. On the flip side, if sales people only show up when it is time to renew a contract, or when an escalation gets hot enough--they will look for any opportunity to avoid doing more business with you.