Welcome to the fun.

Your route is quite unusual, in that most people today don't start with a brand new, currently manufactured, top quality enlarger.

KHB Photographix (in Canada) is a useful resource for many enlargers. Here is their page for your enlarger (note that the model numbers vary depending on which country the enlarger was distributed in): http://www.khbphotografix.com/LPL/LPL4x5.htm

If you don't have the original manual for your enlarger, KHB most likely can sell you one.

They can also sell you other parts. KHB isn't particularly cheap, but they are good.

You will need a negative carrier, lens and lens mount for each format you use. There are often items like that listed here in the APUG classifieds. lightwisps post above links to one appropriate choice, but I would suggest you do some wandering there to get a sense of what is available.

There are a lot of good quality enlarging lenses available used. Some of them are priced so reasonably as to permit trying more than one.

In addition to optical quality, it is worthwhile considering convenience features like illuminated f/stop scales and the ability to quickly and accurately switch between wide open and a chosen stop-down aperture.

In addition to Schneider Componon and Rodagon there are Nikon enlarging lenses in the high quality tier. There are special, top quality versions as well, like the APO lenses. There are also some lesser known brands (e.g. Minolta) and re-badged lenses (e.g. Beseler Color Pro) which are of excellent quality.

There are also lower quality versions made by the high quality manufacturers - best to ask if you have questions.