Rolath is not limited to only classic era spells. The following mechanisms exist to obtain spells from other eras:
Some quests yield spells that were not available in classic. To find our what spells are available through questing simple click on the QuestSpells button at the bottom of your character's Wiki page on your rolath guild roster.
Some of high level spells 49+ that were made available on Kunark Era vendors are available in the Nexus via a vendor named Kunarkia. Head to the nexus to browse her wares.
Advanced Spell Research is available on Rolath and can be used to create spells beyond classic era. Access to these spells for intelligence based casters via a custom research container and drops from level 50+ mobs. Access to wisdom caster spells is also available through drops from level 50+ drops, but you must find the assistance of the proper INT caster to do the combines for you, as you are just not smart enough to do it yourself.
The following links give details for each of the classes:
Wizard Advanced Spell Research (50+)
Enchanter Advanced Spell Research (50+)
Magician Advanced Spell Research (50+)
Necromancer Advanced Spell Research (50+)
Druid Advanced Spell Research (50+)