I only occasionally smoked menthols, but went through a Salem phase. I'm working my way through the Indigo Vapors sampler and their Analog Ice seems really close to what I remember salems tasting like.
Also, when I first started I tried the Vuse gas station big tobacco ecigs. The menthol was very close to an analog, but they have 4.2mg nicotine (ouch) and refill cartridges are pretty expensive.