Back in February I detailed a decent "one book" reference covering Middle East conflicts, AK Interactive's Middle East Wars 1948-1973. This book has a wealth of color drawings which appear to be reasonably accurate based on the original photographs of the subjects I've seen. SabIngaMartin Publications also has a very detailed series of books dealing mostly with Israeli topics, but there are some good references on Arab armor (especially T54/55 and T-62) as well.
Of all of the forces in Fate of a Nation, the Israelis are the most "monochromatic." All of their vehicles are a uniform Sinai Gray - though correctly identifying and reproducing that color was for many years a "holy grail" for the model building and miniature painting community. Sinai Gray not only changed over the years, but tended to fade and accumulate dust making exact reproduction difficult.
paints AMIG0131 and AMIG0132 which are the "real" versions of 1982 and 1973 Sinai Gray respectively (don't ask me why the lower SKU is the later paint...). It also includes paint AMIG0066 "Faded Sinai Gray" which can be used for purely 1967 vehicles in a pinch. The earlier IDF Green (AMIG0068) is also included.
RC096 IDF Sand Grey 1973. The same color is available in their traditional acrylic line as AK792.
Lifecolor also makes paints and pigments designed for Israeli forces. I've found Lifecolor paints a little tricky to use because they start out very flat and if you use a gloss or satin coat on top of them (like you would for pinwashes, etc.), the color can change. Lifecolor paints can be sourced from a variety of stores, but I haven't been able to find a company web presence on its own.
paints called "Yom Kippur War Colors" that actually covers both the 1967 and 1973 wars allowing you to re-create the full range of markings seen in both wars.
So once again we're sort of left with the elephant in the room - Jordan. At this point I haven't found any paints or paint sets which even profess to recreate the colors used by the Jordanian army. There is, however, a 1/35th scale Takom kit of the M47 Patton which includes markings for a Six Day War Jordanian vehicle which references to Ammo of MIG paints. They suggest AMIG0029 which was originally known as "Desert Sand" but is now known as "New Iraqui Army Sand" as the base coat with AMIG0052 "Deep Green" as the disruptive color. They also suggest their Olive Drab Light Base AMIG0972 for the canvas gun mantle cover.
Hopefully this guide will give you a few alternatives for painting up your Arab-Israeli war vehicles that represent more mainline model colors. At this point I plan to start with the Israelis and then I haven't decided whether I'm going with Egyptians or Syrians. I'll likely be using the "Black and White" technique that I modified for my Team Yankee NVA forces (which are... sadly... not quite done) for the Israelis. However, I'll just go with traditional camouflage painting on the Arab nations in the interest of time.