There are 2 Publix grocery stores not too far away ... one of them is at Exit 68 ... go left at the light off the ramp onto SR 535, make a left at Vineland Ave (Rd?) and follow that past the Premium Outlets, the Publix will be on the left.
The other Publix nearby is at the corner of 535 and 192 ... Unfortunately, the 192 exit in the direction you'd need for the Publix is torn up, and I haven't driven it with the construction, so I have no idea if you can even get there easily.
From the Publix on Vineland, to get to Pop Century, make a left out of the Publix parking lot, onto Vineland, then make a right at the first light you come to (I believe it's International Drive South, but not entirely sure) Follow that to the intersection of 535, make a left on 535, then make the first right onto the continuation of I-drive South, then make a right on Osceola Pkwy, and follow the signs for Pop Century.
If you're going to Pop straight from I-4, follow Exit 65 (the AK / Osceola Pkwy exit), and follow the signs on Osceola for Pop. (I'm pretty sure it's a right at the first stop light you come to, across Osceola from the Wide World of Sports complex)