Suggested reading
(Newstead's book being the main recommendation):
GIT:
Newstead,
P. E.
Introduction to moduli problems and orbit spaces.
Tata
Institute of Fundamental Research Lectures on Mathematics and Physics,
51.
Tata Institute of Fundamental Research, Bombay; by the Narosa
Publishing House, New Delhi, 1978. vi+183 pp. ISBN
0-387-08851-2 .
Vector bundles on curves:
dto. and
Le
Potier, J.
Lectures on vector bundles.
Translated by A. Maciocia.
Cambridge
Studies in Advanced Mathematics, 54.
Cambridge University Press, Cambridge, 1997. viii+251 pp. ISBN:
0-521-48182-1
Decorated or augmented vector bundles:
Bradlow,
Steven(1-IL);
Daskalopoulos,
Georgios D.(1-PRIN);
García-Prada,
Oscar(F-PARIS11);
Wentworth,
Richard(1-HRV)
Stable augmented bundles over Riemann surfaces.
Vector bundles in algebraic geometry (Durham, 1993),
15--67,
London
Math. Soc. Lecture Note Ser., 208,
Cambridge Univ. Press, Cambridge, 1995.
Schmitt,
Alexander
A universal construction for moduli spaces of decorated vector
bundles over curves.
Transform.
Groups 9 (2004),
no. 2, 167--209.