Found it. I should've googled it first, but here's the quick, easy answer:
For Alltel phones, simply dial: ##778
That's right, just leave off the last # sign.
On my Alltel Touch, after dialing "##778," the EPST screen came up with three options: View, Edit, and Cancel. Obviously, one wants to select "Edit." This brought me to a screen that read "Please Enter Unlock Code." God bless Alltel, you don't even have to know your MSL, you simply input six zeroes (000000).
This brings up the EPST Edit screen (which reads "Display" on my phone for some reason), which includes such fancy items as your ESN, Life timer, software/firmware versions, etc. However, in the lower left-hand corner (left soft-button) should be the "View Info" button. Touching this button should bring up a drop-down (up?) menu containing a list, which includes "Modem Settings."
Under the "Modem Settings" is your Slot Cycle Index setting. This value is 1.28 seconds multiplied by 2^value (i.e 0=1.28 secs, 1=2.56secs) with 0 fastest, 7 slowest. The default is 2. Changing it to 1 (which will poll towers approx. twice as often) has not noticably affected battery life, so I've read. However, changing it to 0 makes your phone constantly work, which (again, I've read) drains battery considerably. Keep this in mind when changing this value.
Once done, I tapped OK in the upper right-hand corner, and my Touch reset itself. However, after doing so, it was unresponsive, so I soft-reset her again, and it worked fine. Just an FYI.
While researching this topic, I found the following nugget of information that may be of interest to some:
"Changing the ACCOLC (Access Overload Class) to 9 is a good idea. I don't know for sure if any of the carriers in the US actually use it, been told USCC disables it in the switch, but it's better to have it if they do then not. It's the setting that gives the network a "priority level" for your phone. If it's enabled it should only make a difference when a cell is full and needs to start kicking people off. Zero's go first, then ones, etc."
This is found under the NAM menu under the same drop down list that appears when you tap the "View Info" button. I have no idea if this makes a difference, or if it's been tested. Probably can't hurt, though. I was a 0.

Now I'm a hero (9)!