AGI has absolutly zero effect on base run speed.
ALL RACES AND CLASSES RUN AT EXACTLY THE SAME SPEED baring buffs, encumbrance, AA points, damage (low life).
if you are above 20-30% life remaining, and are not encoumbered, then a gnome will run just as fast as an ogre or any other race in between. to say otherwise is just showing how little you know about the game.
lost count how many times the devs ran contests to prove this exact point.
here is a list of some items/spells/AA/etc. that can and will effect the speed of a toon running around norrath:
1. SoW (spirit of the wolf) spell from sham, druid, ranger, BL. potion from sham.
2. SoE (spirit of eagle IIRC) spell from druid also has lev.
3. j-boots (journyman boots) royal pain in the **** quest that gives you clicky boots with just under SoW speed.
4. t-boots (tinkered boots) 5000p from gnome in solA or solB i forget were exactly to buy them. same effect and speed of j-boots.
5. RS AA (run speed) 1-3 give innate ability to run faster at all times, still effected by encumbrance, and low life. with gates expansion you can now push that to 5 IIRC, and that will take you to just about sow speed or a little faster. that you would have to ask someone with rs5.
6. Selo's (bard speed) fastest toon in the game is a bard with high level drum level 55+. these songs only effect the bard and his group.
7. horses and drogma(sp?) the lizards and horses you may see if you have that graphic effect on. they range in speed from just at run speed to up to just under selo's speed.
8. for pally and sk ONLYL their AA point steed. this steed is right at the speed cap, but only slightly under that of a bard, but not really enough to matter.
there are a few other items, spells, effects out there that will increase your speed for running, but AGI is not one of them.