Macro photography: Pana-Leica 45, Oly 60 or Kenko extension tubes?

Want try some Macro photography and I am new to this.

Should I get

• PL 45/2.8
• Oly 60/2.8
• Kenko extension tubes and use any of my present lenses

The PL 45mm is the most expensive of these 3 alternative but it has OIS that might be desireable together with my Panasonic G5. I also have the Oly 45/1.8 so it would make me own two lenes with same focal view which seems redundant.

The Oly 60mm gives me a prime with a new focal length compared to my other primes and it is less expensive than the PL 45mm. It does of course not have OIS.

Or should I start out with extension tubes with my Pana 14-140 or Pana 100-300? This will be the least expensive sollution.

Is IS (OIS or IBIS) needed in handheld macro photography? Or is everybody using tripods anyway to get sharp macros?

Will the OIS in any of my zoom lenses be any good/work together with extension tubes?