I don't know exactly what you mean by linking. You pronounce the two words separately, but without stopping between them, if that's what you mean. I would call it more of a transition than a link, but perhaps the two are the same.
The "...ge sh..." of "image shack" has
d +
zh +
sh. The
sh is just a devoiced
zh, so it should be fairly easy to make the transition. It's the same principle that you use in a transition from
z to
s or from
v to
f. (He ha
s six; you ha
ve four.) Your lip position and tongue position remain the same through those transitions. Spend less time on the first of the two so that it sounds like the
sh sound starts quite soon after the
zh. If you do it right, you will
almost get a
d +
sh without the
zh, but the
zh will be there very briefly.
"fish sauce" is different. Both
sh and
s are unvoiced, so you have to move your lips and tongue a little to make that transition. But here again, you "slight" the first sound a little bit and "rush" to the second.
Note that if both sounds are the same, don't stop. Make the two into one sound without any break.
Swi
ss steak = swissteak -- never swissuhsteak or swiss steak.
Sorry, I don't have a website to recommend.
CJ