I'd recommend using the templates in Word. Word lets you do anything with text and position graphics, so there's not much else you'd need Photoshop for.

Launch Word, then go Tools > Letters and Mailings > Envelopes and Labels.

Click Labels tab

Click Options

Make sure it's set to 'Laser and Ink Jet' printer, not 'Dot Matrix'.

Then there's a label Products drop-down menu with a list of label manufacturers.

Select one, and it gives you templates for many of their standard labels.

I find Avery's J8165 very handy; 8 to an A4 sheet so they're big enough to catch an eye on bus or vending machine, but small enough to be pocketed. And being Avery rather than Staples own brand or whatever, the adhesive is really strong so the sticker stays around a while.