Yeah, English "sh" (which, yes, is [ʃ]) is a really nice sound. In general, I like fricatives and affricates made in that general area of the mouth.

In response to your side noteː

• [] is phonetic transcription, used for exact sounds. For example, I say the English words "kin" and "skin" like [kʰɪn] and [skɪn]. This transcription can vary between dialects. For example, I say Latin like [læʔn̩], whereas someone else might say it like [latʰɪn].
• // is for phonemic transcription, used for phonemes. A phoneme is sort of a set of sounds that distinguishes words from each other. For example, "cat" and "bat" are seperated by the phonemes /k/ and /b/. You can't swap the consonants without changing the meaning, so they're said to be distinct phonemes. A phoneme can have several different realizations — for example, /k/ can be [k] like in "skin" or [kʰ] like in "kin" — but these variants aren't used to distinguish words. Thus, they're said to be allophones of a single phoneme.

As for resources, I don't fully remember how I went about learning IPA, but I'd recommend these old videos by Artifexian on place of articulation, manner of articulation, and voicing (the three main elements of any consonant in the IPA), as well as his video on vowels.