This will work as well. I use either 5" or 6" needle nose pliers.
http://www.modeltrainstuff.com/Excel-55560-5-Needle-Nose-Pliers-p/exc-55560.htm
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
I use the spike pliers that Maxman linked to. I also use these for small spikes.
I also found in my local hardware store a pair of needle nose pliers with agressive serrations on them. The only markings on them is 'china'. They work too.
I think you need a couple of different types/styles depending on what you are spiking and what type/size of spikes.
http://www.micromark.com/Spike-Insertion-Plier
Does anyone make spike driving pilers for HO gauge rail spikes?