I've had this same problem, embarrassing, huh! What I finally learned to do is title each task with the name of each client (I'm a lawyer, there are lots). Each client also usually has several projects at once. So, if Mr. Jones' revocable trust is one project, and call sally is the next action on that project, the title of the next action looks something like: "JONES: revocable trust - call Sally re status." (There might also be "JONES: irs litigation - write brief" etc.)
After I've left a message for Sally, I put info about date of message, etc in a note attached to the todo item. (The notes attached to teh todo items get stacked up with the timeline of how the project got done - often useful later.)
When my boss comes in and says "Where's Mr. Jones' trust?" I use the search feature on my clie to search for "jones", and can usually spot the item immediately. I'm using that search feature more and more, and have learned that titling the todo items in a uniform manner seems to help alot.
Hope that helps.