regex only on certain extensions / find / sed

Log from IRC server Freenode (IPv6) channel ##Linux.

<me> I'd like to apply a regex only to certain files, with the extension .php and .inc how could I do that ?
<me> could somoene help with my command problem ?
<Element14> me: sed -i REGEX *.php *.ini ?
<me> Element14: thank you kindly ! that's a big help
<me> I'm trying to get the files in a certain directory with the command "grep -r '1969' *.php *.inc > /grep_1969" but I keep getting the error : grep: *.php: No such file or directory
<iasc> me: use find. http://wooledge.org:8000/UsingFind

Here's there command I've been using : find . -type f \( -name '*.htm*' -o -name '*.php*' -o -name '*.inc' -o -name '*.tpl' \) -exec grep -H 'REXEX' {} \;