I would encourage you to consider that solutions are predicated on the exact need - the more laser focused you are on your specific needs should reveal the solution best for you.
For example, larger firms with hundreds of producers spread out over contiguous markets will naturally require a robust CRM system to input prospects, manage the sales process, estimate future revenues, and last but certainly not least...producers chasing the same prospect which always leads to lot's of chaos. So the SalesForce's, Sugars, Zoho's, etc., etc., serve that need quite nicely.
For individual contributors within organizations that have no CRM, or for solo-practioners, a basic CRM can be contributory to efforts for the tech savvy and those committed to not only learning the CRM but consistently using the CRM over time.
Short of that - an excel spreadsheet that identifies prospects, contact info, estimated commissions, the stages of the sales process, and has formulas that provide likelihood of success for each prospect and rolls up an overall 'gross commission' value and an 'estimated commission' value along with a space to type in 'next steps' so you don't forget any action items is all you need.