Explore the city over the weekend? (Johannesburg)

Hi all,
I literally just arrived at Joburg this morning! So far so good =)

I live in London and came to Joburg on a secondment and I'm staying here till mid-Nov.
My office and accommodation are based in Sandton.

I've got work friends but I'm looking for someone who is new to the city to explore the city together. Would like to do some day trips outside Joburg too if anyone is interested.

I'm 31 years old female (married but husband is back in London), if there is anyone out there who is in a similar situation, please get in touch, let's form a little group so that we can hang out =)