I think sliding is more of a personal choice by the player rather than tune dependent. It can also get annoying pretty quickly, IMHO.
Nevertheless, here's a great tune from Kirk McGee that features some essential slides: slippery-hill.com/content/lafayette
Also, Arthur Smith's playing was quite bluesy and he used slides a lot. More recently Ralph Blizard, who was an Arthur Smith fan, used a lot of slides.

PS - Tommy Jarrell was also a great slider, which went well with Fred Cockerham's fretless banjo playing. Here they are playing "Sally Ann"
slippery-hill.com/content/sally-ann-2

Here's a really squirrelly one from Arthur Smith: youtu.be/BPARMhSVObI?si=xSar0ak6pxzSotA9

I remembered that I'd posted a recording of "Western Country" with me fiddling that has some sliding, especially up to the F# (the third) on the first string.

There are so many places slides could be used that it’s hard to recommend a particular tune for practicing as an especially good example. You might do just as well playing a tune of your choice and adding in slides in different places to see what effects it produces.

The subject of sliding is interesting. It’s a form of ornamentation but also seems to be somewhat tied to time period. As in so many other areas and eras, fiddling of the “golden age” followed some of the ornamentation used in European music that preceded it. At that time, the classical music was still heavily influenced by the romantic era, and the great violinists were known partly by their stylistic choices in doing portamento. It’s therefore no surprise that slides showed up in fiddling of the time as well. But as time passed, the use of slides gradually fell out of fashion to a large extent. In fiddling, the use of slides gradually decreased reactively. There’s not as much sliding in current fiddle playing, as emphasis has been placed elsewhere. Throw a few slides in at a jam where the others aren’t sliding and you’ll probably get a few glares.

Sliding is a good tool to have in the bag for ornamentation, but just be careful about its use, as groups of players and modern audiences are not as receptive to it as they used to be.

Thanks Doug for the advice and examples ! And Rich for diving deeper into the history of using slide notes !
Today I tried to speed up the tune I just learned and same time use slide notes. It now sounds like something else, something very 'me' instead of the tune version I used as an example . I made sure however that the slide notes are not 'too much ' , but I hear also I need more practice to have more 100% exact rhythmic symmetry here,not sure if that's because of speeding up or sliding, probably the combination of both. (That's the biggest challenge of all, to finetune a tune so that it sounds like it's being played with utmost precision regarding the timing )

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Originally posted by Quincy

 but I hear also I need more practice to have more 100% exact rhythmic symmetry here,not sure if that's because of speeding up or sliding, probably the combination of both. (That's the biggest challenge of all, to finetune a tune so that it sounds like it's being played with utmost precision regarding the timing )

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That's a good point. Slides are a useful ornament and they add character, but you have to be careful in how you execute them, as they can easily throw you off rhythm or they can confuse the audience about where beats fall. Especially in fiddling, a lot of the slides are pickups to the note, so they start before the beat and then hopefully line up with the downbeat when they hit the target pitch. 
 

You could perhaps think of it like throwing a curveball. You want the ball to arrive in the strike zone at the right time, but you put spin on it in a specific way in throwing it so that it'll follow a sidewise arc as it flies to make  its path harder to follow. The slide is like the curve of the ball. If you can get it to the right place on time it will be likely to work; if not, it's a penalty. Beware Miles Davis' warning about timing!