Seeking Makefile style suggestions

I'm incorporating bits from various shell scripts into a central Makefile
for a largish project.  I've never written a Makefile more complex than

  foo: bar.h

before and I'd like to learn how to do this the "right" way; that is, more
experienced users won't laugh at my clearly "un-make-ish" habits.

Right now, a common task is to make sure that all files in our Subversion
repository have the correct properties set.  I do that from a shell
script like so:

  find $(CURDIR) -name '*.py' \
        -execdir svn propset -q svn:keywords 'Id LastChangedDate LastChangedRevision' {} \; \
        -execdir svn propset -q svn:executable '*' {} \;                                         \
        -execdir svn propset -q svn:eol-style native {} \;

Is it idiomatic to do this by putting that in a target like so:

  svnprops:
        find $(CURDIR) -name '*.py' \
                -execdir svn ....

or is there a more "native" way I could approach this?

Also, I'd really like to refactor all those identical calls into a
variable that contains something like "svn propset -q", but I'm not sure
how to get Make to split such a string into the command and its arguments
instead of a command named exactly that.  For example, this snippet:

  foo: TESTVAR = "echo this is a test"
  foo:
        $(TESTVAR)

tries to run a command called "echo this is a test":

  $ make
  "echo this is a test"
  /bin/sh: echo this is a test: not found
  make: *** [foo] Error 127

which happens not to exist on my system.  Is this the wrong approach or
am I missing something?
-- 
Kirk Strauser