[Beanamir of Gondor]

If you'd like to do the translating on your own, there's a really great book by Ruth S. Noel called "The Languages of Tolkien's Middlearth". It's got all the stuff that's in the appendices of RotK on Tengwar script, but a kind of bitty guide to writing Elvish script and scripting Sindarin and Quenya into Tengwar, which is a wholly phonetic script. (Noel's book also happens to have a full glossary of any and all non-English terms Tolkien used in his novels.) I've tried translating and scripting stuff multiple times with Noel's help, and though it's a little tricky at first, once you get the hang of how the vowels and sounds work, it's really fun. You can probably find the book in multiple places on the internet for purchase, and a lot of college libraries (believe it or not) carry it.

The website YaTT (Yet Another Tengwar Tool) has a downloadable tool to transcribe text from words into Tengwar script. I've never tried it, but I guess it's worth a shot. The folks there also have downloadable Tengwar fonts, though you said you were wary of that.

I would check the website The Council of Elrond: they've got a pretty good list of sources you can try on the next. (I personally recommend Noel's book, because even if you're not entirely sure if you've got the script perfect, then at least it's done with your own hand!)

Anyone else have better suggestions?
Good luck, jenny! Welcome to the BD.