Past Sarutabaruta was definitely the best spot to do elementals. There's actually 4 SMN yags there. You can easily cycle the bottom 3 with 0 problems. Only the northmost one was kind of annoying, since he loves to surround himself with other yags (and I swear he took longer than the others to summon an Ele).
Either way, any level 80 BLM/SCH/RDM/PUP can easily cycle trough all 4 with 0 difficulty. Just one-shot them as they pop, and you won't aggro the master. Can easily take 50+ Ele's with a single person, meaning that it would take you 3 lightsdays to finish.
It's obviously a bit harder if you don't have those jobs. Asking for a friend or trying to leech off someone is probably a much better option than trying to kill 150 of those on WHM <.<
Edited, Aug 5th 2010 11:30pm by Drakonite
It is better wither to be silent, or to say things of more value than silence. Sooner throw a pearl at hazard than an idle or useless word; and do not say a little in many words, but a great deal in a few.