The ornamental design for a tool handle, as shown and described.
FIG. 1 is a perspective view of from the front end showing the left side and top of the tool handle, embodying our new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is an enlarged elevation view of the front end; and,
FIG. 6 is an enlarged elevation view of the back end.
The broken line features jutting outward from the handle form no part of the claim. The broken line shaft and tool end illustrate environment and form no part of the claim.