Im just wandering if there is any possible way to find Himmler's diary
Himmler's duty diary for the years 1941/42 has been edited by among others Peter Witte and Michael Wild and can be purchased on Amazon, provided you speak German.
The duty diary of Himmler from the years 1938-39 and 43-45 is currently in the Central Archive of the Russian Ministry of Defense and a team consisting of Dieter Pohl and Matthias Uhl are currently working on editing and publishing it with support of the GHI Moscow. The plan is to publish it this year.
The years from 39 to 40 are still missing but it is not unlikely that they too will be found in the Russian archives at some point in the future since the GHI is (or at least was since now political circumstances have changed considerably) working on digitizing all German documents in Russian archives concerning the Second World War and the Nazis.
However, the duty diary is not a Goebbels style collection of Himmler's thoughts. Rather, it is an official notebook in which Himmler wrote down his meetings, phone calls, and official engagements throughout the day. While it does contain some short notes on each of these meetings, the interest of historical research in this primary document is more due to the fact that it allows us to reconstruct decision making in the Thrid Reich when placed in the context of other documents since we can now know who Himmler met when and through other documents what the outcome of these meetings were.
If you are looking for a Goebbels style recollection of thoughts on various matters, such a thing does not exist because while Himmler had a duty diary and an annotated reading list, he himself said he was never cut out to be a meticulous diarist.
Sources:
Peter Witte; Michael Wildt/ Martina Voigt/ Dieter Pohl/Peter Klein/Christian Gerlach/Christoph Dieckmann/Andrej Angrick (ed.): Der Dienstkalender Heinrich Himmlers 1941/42, 1999.
Currently the German site Bild.de has excerpts available to the public. The diary is naturally in German and hasn't been translated and I'm not sure that is likely to happen in 2017. It's the cheapest and easiest way to get the portion that has been published so far.
Here is the site that you can go to if you want to read it. It is 99 cents a month for access (.99 euros), but you'll have to find someone to translate them for you.
http://www.bild.de/bild-plus/storytelling/topics/storytelling/wie-bild-den-kriegskalender-von-heinrich-himmler-entdeckte-44878926,var=x,view=conversionToLogin.bild.html
Most big U.S. cities have a German cultural center that offers German lessons for a fee. You can try to ask them to translate it for you but I doubt that they would. Hitler's Mein Kampf has only recently been made available in Germany and most Germans are emotionally allergic to reading anything like that. Himmler's diary is much worse as you probably know. It's not like Rommel's book at all.
Edit: Marga Himmler's diary can be found here: http://www.fpp.co.uk/Himmler/diaries/Fr_Himmler_Tgb_1937_45.pdf
Second edit: Apparently a few British journals are working on a translation of the excerpts that appeared in the Bild. Should be available later this year, but dates aren't readily available.