Dedicated personal assistants are great in theory, but unless you spend all day managing 'em they inevitably'll end up sitting on their ass costing you money, and if that's what you wanted you'd stop pulling out. For personal assistance fitting your part-time needs, hit up Fancy Hands.
A virtual PA service co-based outta NYC and Portland, OR, Fancy let's you offload menial tasks on to their worldwide network of remote desk-jockies for a modest monthly fee, the payment of which hopefully one of them can schedule, cause you have no time for this crap. Allotting 15 monthly tasks per membership, simply email Hands a request 24/7, give 'em a deadline, and they'll auto-delegate it to the appropriate member of their globe-spanning crack squad, which includes everyone from part-time actors, to retired lawyers, to former ChiChi's employees...wait, you can't get herpes over email, right? Acceptable requests include pretty much anything that can be handled remotely: securing dinner ressies (told you!), locating quality home service folks (cleaners, plumbers, painters, etc), sourcing gifts for coworkers and semi-loved ones, and even performing "research [on] an aspect of a blog post" -- hey, somebody needs to figure out what's meant to be funny about LOL Catz.
Currently FH is abstaining from handling tasks that require providing your credit card info, but they plan to roll that out in the near future, so you can be the one sitting on your ass costing you money.