I am looking for an extensive source (often called "table of integrals") listing primitives of various classes of functions including the "elementary" ones (rational functions, functions involving radicals, ...), indicating also a/the convenient method to obtain the result.
For example, one entry could be similar to
$$\int x^2e^x\mathrm{d}\!x=e^x(x^2-2x+2)+\mathrm{Constant}$$
with the indication:
$$\textrm{By parts}\; (x^2,e^x); \textrm{by parts}\;(x,e^x)$$
or "integrate by parts two times" or just "by parts".
If there is a substitution to perform, it should be explicitely indicated, etc.
A free and user friendly computer program would also do. But for example Wolfram Alpha doesn't seem to "do the steps" or to give indications on the procedure.
Edit. Please note that
1) the example integral that I wrote above is, indeed, merely an example, not an indication of the intended complexity (or not) of the integrals!
2) I am not looking for textbooks that explain integration techniques (though I realize the distinction may not be sharp). I am merely looking for a list of primitives, endowed with indications about how each result has been obtained. Hypothetically, to explain how to obtain the primitive in my (easy) example above just literally one or two words may be enough.
3) I do not compute integrals all day long. I may very well forget which is the right substitution to perform in a certain instance. I am just looking for an easy way to get: "this is the result ok, and -aha- this is the method. So if I wanted to do the integral by myself I would know, without trying a bunch of useless substitutions/methods".