Well there are lots of good recommendations here....I sure wish we had a Running Room here in Pet.
As for me I have been recently (over the past 4 years) getting into long distance running and the half marathon (don't even say it Al

). As such the most important thing is a good pair of runners, which has already been discussed at length.
I normally wear Reebok running sneakers...until I found out when I was shopping for a new pair that they, alas, are getting out of the runners department.
So I had to start looking for a pair that would suit me. I went to the local Sportschek with an open mind.
As luck would have it the girl that served me was a marathon runner that I recognised and we began a good fitting process. tried on literally every running shoe in the store....
My frau was about to kill me after almost 2 hours.
Left the store with a pair of Nike Air Moto 3's...but with a bit of reservation in the back of my mind. I know how my feet feel in my old runners...this was really different.
Anyways next morning went for a little jog...5 km, somewhat a breaking in run, and the shoes felt fine. The day after a bit longer of a run, 7 km...shoes felt a bit wonkey so I adjusted them a couple of times during the run...tossed it to the shoes breaking in.
Day 3 and it was a long run day, minimum of 10km or an hour long, whichever came
last. So after about 8 km my right foot was on fire ( and I was adjusting it constantly)....there was something wrong and I wasn't looking forward to taking off the sneakers at all.
Needless to say there was no skin left on the outside of baby toe and the shower was torture ;D
Went back in the same day to the retailer mentioned above and complained...so another fitting was done and I walked out with a pair of Nike Shok 2:45's (freakin expensive!)
Went for a run a couple of days later (after my toe healed up a bit) and it was like night and day. Feet felt really good and there was very little shock going up my bad knee, as was the case with other shoes I've tried over the years.
The girl was amazed that they were working so well for me, she was completely against me getting them for some of the reasons mentioned above, pronation (sp?) etc.
Like it was said earlier in this thread...don't go for name brand, go for the shoe that works for you.
I love my Reeboks (still have them as walking shoes) but now I love my Nikes....and that will probably change with the next set I buy.