There are adapters which will allow for one IEC pc to feed two others. it has the male IEC end, with two female NEMA (wall outlet) ends. $10.
Personally, unless that power strip of your's is a real doozy, I'd buy me a nice power filter/conditioner like Audio Magic, PS Audio, or Running Springs, etc., and plug my front end items into it, Use the strip then to feed the amps.
or... if it's your wall/home, turn the single duplex outlet into a double duplex outlet, and in the doing, step up the outlets. I'd also advise you use perhaps, two ckts. A different one for front end stuff and another for amps & preamps..
However, if everything runs ok as is... or if it's a dedicated ckt to begin with, simply cutting the wall opening to a bit larger one, adding/replacing the outlet box, adding one more duplex receptacle and a foot or so of Romex for a pigtail which will feed both outlets, should run around $10 and take about an hour or less to do.
Now you do know getting an electrician will be best and I've got recommend it here... but I was once and have done this with my eyes almost completely closed. it ain't that hard. it all comes down to how much draw these new amps will have plus what's on the ckt already.