It is not too different from running other RPGs on Roll20, depending on your usual style. I find for VTT it can help to provide visual aids to describe some of the less traditional monsters that pop up in sword and sorcery settings because you have no miniature to look at and only a tiny token to represent it on the board.

Also I keep a good number of pre-prepared character sheets and tokens of npcs/monsters/animals in your library so you can drop them down at a moments notice if your game goes in an unexpected direction (keep a list of good generic npc names too).

Here's another I've just started writing to use in my first session of the new year:

​You've tracked the raiders to their hideout, a fortress that sits atop a plateau. Within, a host of murderers and the girl they kidnapped to use in their fell ritual. If you hurry she may still be alive...

Six months ago, Khadar the Exalted, lead a coup to seize command of a group of bandits known as the Exiles. He threw the burning bodies of the loyalists from the high walls of the fortress before converting the surviving bandits to the worship of Zaggath, the Lord of Fire.
Since then they have raided the border towns and villages surrounding Halakh. In each raid the Exiles have taken prisoners to use in their dark rituals, usually young women. This continued until three nights ago when Khadar managed to kidnap the daughter of a local high priest. The High Priest subsequently offered a generous reward for the safe return of his daughter, and another for the head of Khadar!

Right now you are scaling the near-sheer cliffs of the plateau in the hope of finding a way inside and rescuing the girl before the ritual begins!

If you have any ideas or suggestions for what I could use in this adventure I'd love to hear them.

Now I've been thinking about how I would actually use this mechanic in my game, I realise that a better idea is that when they wish to conduct research you (The GM) make a task roll on their behalf (adding their mind score and any relevant careers) to see how well they translate/transcribe the original text with more powerful spells/devices being more difficult.

For example, if a player failed task roll to learn the "Plague of Undead" spell from Phesipho's Scripture of Desecration, the GM could decide that should the task roll fail, the player has unknowingly transcribed the ritual incorrectly so that when the player tries to summon an army of bloodless to do his bidding during an adventure he causes the dead to rise across the region without being able to control them! So now the players are left with not only their original task, but now must contend with the hordes of flesh hungry undead!

Ha! That does sound like a cool adventure idea. A sorcerer summons a demon and tries to bind it to his service with its true name. Only to find that its name is in fact not "Walter", leaving it to run rampant!

Having recently inducted some new players to BoL, I thought I might talk about how I handle sorcery and alchemy especially for new players. As a house rule I generally don't allow players in my games to start with Magician or Alchemist as one of their four starting careers (unless they have a really good idea for it!). I prefer to let them buy it later with AP so that they have time to learn how to use the basic mechanics of the game first, as sorcery and alchemy can require some pre-game prep on the players part which may be difficult to do.

This brings me to my second point; Tomes of Knowledge! These serve as a way for existing player characters to "discover" sorcery or alchemy, allowing them to buy into the career. These are typically rewards I place hidden about in dark dungeons and wizard towers for the players to find and they contain recipies and spells that the player reading it can unlock by spending AP to conduct research between adventures. Here are some rough examples I've made: 

C = Common 
U = Uncommon
L = Legendary
M = Mythic 
1st/2nd/3rd = Magnitude

Furi's Folio of Thaumaturgy(Alchemy), an ancient tome bound in yew plates inlaid with iron. It once belonged to the thaumaturge Furi, who vanished in the Temple of Mist. (Requires Mind 1)
-Sleeping Powder(C)
-Healing Salve(C)
-Blackpowder Bomb(U)
-Armorbright(U)
-Firmament Stone(U) 

The Tome of Giants(Alchemy), a large tome written in illuminated script upon linen pages. It was written by a monstrous goddess for the illustrious alchemist Gwali. (Requires Mind 4)
-Potion of Giants Strength(U)
-Bottled Lightning(U)
-Lightning Gun(L) 

Phesipho's Scripture of Desecration(Sorcery), a set of etched glass plates contained in a gold coffer set with silver pearl. It is said to be haunted by the ghost of the great necromancer Phesipho, who fell at the battle of Hydral Chasm. (Requires Mind 2)
-Summon Rat Swarm(1st)
-Raise Dead(1st)
-Drain Life(2nd)
-Summon Ghost Ship(2nd)
-Plague of Undead(3rd) 

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