That reaction gives a bit more to work with.
Reformed and Lutheran are the major traditions going back to the Reformation. As such they share a general approach. They're also, in my view, the most coherent theologies in the Protestant church. Lutherans and Reformed had to create a whole theology at once, because they were trying to do a major rethinking of all of theology in splitting off from the Catholics. Other churches started because of various concerns or insights, but don't necessarily have this complete theological vision. Even in their more liberal forms (which I'm part of) I find the Reformed and Lutheran churches more theological somehow than other Protestant churches.
Between the two, in my view the Reformed tradition tends to be more logical, and the Lutheran tends to maintain a bit more paradox. That's not necessarily good or bad. After all, humans don't fully understand God. So sometimes a view that's too logical can oversimplify the truth. But there's a lot of commonality between Reformed and Lutheran.
But if you're looking for churches today, be aware that (at least in the US) there are two major approaches in both the Reformed and Lutheran traditions. The churches that stick closest to the original theology coming from the Reformation are "confessional." Those that use critical Biblical interpretation and accept ideas of history and science that don't agree with literal interpretation are "mainline."
Typically mainline churches ordain women and gays, while the confessional churches don't (though some may ordain women to some offices).
Most churches from the Presbyterian / Reformed background today are mainline. For the Lutheran churches it's about 50 / 50 I think. If you've heard R C Sproul, he represents a conservative, confessional form of Reformed thought.
I'm going through all of this because I don't want you to think that if you walk into a church labelled "Presbyterian" or "Reformed" you're always going to get theology similar to Sproul's. You aren't, because he's from a confessional church and most Presbyterian churches today are mainline.
If you're willing to do some reading, take a look at the Westminster Confession,
Westminster Confession of Faith (1646) - no frames, and the PCUSA's Declaration of faith,
A Declaration of Faith - Introduction. That will show you the two approaches in their Presbyterian versions. Westminster is used as an authority by the confessional churches. The PCUSA declaration is more typical of mainline churches.
You'll see that Westminster tends to be more precise in terminology, but uses lots of terms and forms of thought from the Christian tradition that aren't directly Biblical. The PCUSA declaration tends to stick with Biblical terms, but isn't as precise, and the Biblical terms are often understood in a modern sense. The PCUSA is more willing to tolerate differences in interpretation. These differences are typical of the approaches.
The same differences exist among the Lutherans, except that as a Presbyterian I don't have Lutheran statements handy to show the two approaches there.
If Sproul has attracted you, he is a representative of the confessional point of view, using Westminster as its authority.
There are different sets of denominations reflecting the two approaches. For Reformed, here's a list of denominations in North America. (If you're not from here, please say so.)
List of Reformed denominations in North America - Wikipedia, the free encyclopedia. It uses "liberal" for the mainline denominations. I believe the rest tend to be conservative, though they seem to be using "orthodox" to mean that they stick to the traditional creeds and "evangelical" to refer to a less credal conservative viewpoint. Sproul would be classified as "orthodox."
On the Lutheran side, I believe the ELCA (Evangelical Lutheran Church in America) is the mainline version and the many other denominations are conservative. (Because conservatives want to maintain fairly precise theological standards, those churches tend to fracture when there's a disagreement. So there are a lot more conservative than mainline churches in each family, but the conservative ones are normally smaller.)