I have been into flying for years but something I can't figure out is how do I, as a pilot, know if an airport I am going to has ILS, which runways would have it and why do only some have it but the other side of the same runway does not? (I.e. RWY 9 has ILS but 27 does not and they use same frequency.) Do I have to look for something specific like localizer vs localizer DME etc.?
There are published instrument approach procedures for all airports served by an instrument approach. These are commonly referred to as Approach Plates. (In paper form). Your local pilot shop should have them, or you can order online.
Just look in the section for the airport you are going to and all the available approaches will be there. Browse to the ones for the runway in use, and choose one that matches your equipment capabilities. That’s the one you should request with ATC. (After you get your instrument rating of course!)
If you have a tablet EFB application and the appropriate subscription they can be brought up on your device.
Your question about ILS glide slope not being available on the reciprocal runway has probably been answered before, but the best answer is because it requires a separate transmitter, which costs more money, and needs to be justified based on need and usage. (I.e. Perhaps the runway without GS is favored by winds when weather is typically clear...)
A good place to start getting the info you seek is The Airport/Facilities Directory and NOTAMS give you the actual availability on a day-to-day basis.
Some RWYs have a Localiser BackCourse approach - LOC BC RWXX;
If RW 9 has an ILS, the same Localizer has a Back Course (BC), that lies on RW 27 Approach centerline. Every Localizer has a back course. Obviously it will have the same frequency of the reciprocal ILS as it's the same transmission.
A BC does not constitute an ILS approach, it is a non-ILS approach, or in other terminology it is a non-precision approach. It has no vertical guidance. Minimums therefore would be non-precision.
Here is a chart for a RW08 ILS, and below that, it's reciprocal RW26 LOC BC:
Another option that you may be looking for, is the "Circle to Land" where you would get a clearance like " Cleared for the ILS Approach 09, Circle To Land 27".
Both the above come with their caveats such as, but not limited to:
- BC - procedures/systems to eliminate reverse-sensing of the Localiser deviation bar or localiser 'diamond' during BC approach. Generally, on current generation big jets, as long as the FC (Front Course) of the ILS is set while flying the BC the sensing will be correct while flying the BC chosen from the FMC DATABASE by name. This maybe counter-intuitive to the set-up/flying of a VOR course. In some airplanes the Back Course is set and a BC 'button' is used to ensure correct sensing. You need to check with the manuals and Company procedures.
- Circling - setting of Circling Altitude instead of the ILS Decision Altitude as the Decision point by which you have adequate visual reference to continue or go-around.
- Circling - may need FAA approval/acceptance as a permitted procedure.
Unless you've already been regular with these procedures, there's never enough prep/ practice you can do.
If you are trying to find an easy way to locate ILS approaches in your intended area of flight while flight planning, you might try using web tools such as SkyVector. Tapping on any point on the sectional or chart you are using will bring up a list of points of interest. Tapping on an airport name will bring up a list of Instrument Procedures for that airport. It will be easy to find ILSs from there. In the cockpit, where internet access will be sparse, a dedicated tablet app like ForeFlight will do similarly.