Now ya' guys have been crossing into my area!
(Sorry Knot!)
I've carved several of the exotic woods and I can tell you that Ruler2112 and prexaspes are both correct about the "Ironwoods". Several woods that fall in this catagory are Rosewood, Zebra wood, Purple Heart, Blood wood, Pau Fero, Babinga, and my favorite is Bacote.
The dust from these can cause an allergic reaction on the skin that looks like a severe rash and itches like HE**. A respirator is highly recommended! These all will produce a beautiful walking stick, if you can afford them, have the proper tools, can find a long enough piece with a nice grain, and have patience when working with them. (Bacote can change grain patterns with 1 swipe of a sanding drum, so be warned.) I wouldn't advise any of the Ironwoods due to the weight of the wood.
Diamond Willow, while it is NOT straight can also make a BEAUTIFUL walking stick, that is strong, durable, and affordable. It's just hard to find the right piece!!!
Rock Ash is easier to come by back east and can be easily formed for the handle. We used to use it at Christian Bros. Hockey Sticks for handles. I tested a couple thousand one summer and can tell you, you need to check the bend in the stick for strength. It's main weakness is in the grain spliting and the split traveling up.
BC, I still have chunks of all the "exotic" woods I named and a few more and I can tell you, I paid by the board foot for all of them. Albeit, some were in the range of $45 a board foot. But, when your using them for pistol grips that you are selling for $45 - $99 a set, it can pay off. On average, I could make a set for an auto in about 2 hours, and a revolver in 4 hours. I sold them as fast as I could make them and got more pleasure at the sight of the finished product.
Unfortunately, I had to quit making them when I had my last nose rebuild and just never got back into making them. I still have the wood blanks, some chunks, and most of the tools, so, one day, I may take it up again as a hobby.
Harder
BTW, my favorite "normal" wood to work with is Oak or Lace Wood (which is similar to Oak, but with a lace pattern in the grain).